A constant perturbation method for evaluation of structural diversity in multiversion software

In this paper, fault simulation is discussed as a test method for diversity assessment of multiversion software and data flow perturbation is used as a main technique for implementation. More specifically, constant perturbation is introduced as a specific example of data-flow perturbation. Some quantitative metrics are proposed for the description of software diversity, and the parameters needed to calculate the metrics estimated by fault injection experiments. A case study is presented to illustrate that the diversity metrics are appropriate, and that constant perturbation is a practical fault injecting technique to estimate parameters necessary for assessing diversity.